Make Found an encoded list token string in a scalar string context easier to debug

[DanielMSchmidt]

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Description

Currently those errors come with stack traces like this:

    /Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:127
          throw new Error(
                ^
    Error: Found an encoded list token string in a scalar string context. Use 'Fn.element(list, 0)' (not 'list[0]') to extract elements from token lists
        at resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:127:13)
        at Object.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:70:16)
        at resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:244:39)
        at Object.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:70:16)
        at resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:244:39)
        at Object.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:70:16)
        at resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:244:39)
        at Object.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:70:16)
        at Object.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/private/resolve.ts:244:39)
        at Function.resolve (/Users/danielschmidt/work/demos/cdktf-aws-networking-demo/node_modules/cdktf/lib/tokens/token.ts:244:12)

Adding information like which construct / property caused the error would be great, especially for users changing a lot of code at once, it's super hard to pin point where the error stems from

References

[daiwei920]

It is not a bug, I found the solution:
import { Fn } from 'cdktf';
Use Fn.element(this.vpc.subnetIds, 0)
More detail, read: https://www.terraform.io/cdktf/concepts/functions

[github-actions]

I'm going to lock this issue because it has been closed for 30 days. This helps our maintainers find and focus on the active issues. If you've found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.